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Oblasser, C., McCourt, C., Hanzal, E. and Christie, J. (2015). Vibrating vaginal balls to improve pelvic floor muscle performance in women after childbirth: a protocol for a randomised controlled feasibility trial. Journal Of Advanced Nursing, 72(4), pp. 900-914. doi: 10.1111/jan.12868This is the accepted version of the paper.
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1
Vibrating vaginal balls to improve pelvic floor muscle performance in women after
childbirth: A protocol for a randomised controlled feasibility trial
Abstract
Aim. This paper presents a feasibility trial protocol the purpose of which is to prepare for a
future randomised controlled trial to determine the effectiveness of vibrating vaginal pelvic
floor training balls for postpartum pelvic floor muscle rehabilitation.
Background. Vibrating vaginal pelvic floor training balls are available in Austria to enhance
women’s pelvic floor muscles and thus prevent or treat urinary incontinence and other pelvic
floor problems following childbirth. Nonetheless, there is currently little empirical knowledge
to substantiate their use or assess their relative effectiveness in comparison to current standard
care, which involves pelvic floor muscle exercises.
Design. Single blind, randomised controlled feasibility trial with two parallel groups.
Methods. It is planned to recruit 56 postpartum women in Vienna, who will be randomised
into one of two intervention groups to use either vibrating vaginal balls or a comparator pelvic
floor muscle exercises for 12 weeks. As this is a feasibility study, study design features
(recruitment, selection, randomisation, intervention concordance, data collection methods and
tools) will be assessed, and participants’ views and experiences will be surveyed. Tested
2
performance as reported by participants and measured by perineometry. Descriptive and
inferential statistics and content analysis will serve the preparation of the future trial.
Discussion. The results of this feasibility trial will inform the design and conduct of a full
randomised controlled trial and provide insight into the experiences of women regarding the
interventions and study participation.
3
Why this study is needed
Vibrating vaginal balls are used with little scientific evidence on their effectiveness
If effective, vibrating vaginal balls could enhance pelvic floor muscle training choices
for women after childbirth
A robust randomised controlled trial needs careful preparation and will be informed by
the proposed feasibility trial
Keywords
Feasibility studies, midwifery, pelvic floor, vaginal balls/cones, perineal care, postnatal care,
4 INTRODUCTION
Pelvic floor health is an important issue for women worldwide, and the impact of pelvic
problems on women´s lives can be considerable. Pelvic problems impair women´s quality of
life, women feel in a vulnerable situation and experience powerlessness in living with an
unpredictable body; this negatively affects their intimate relationships, work and social
activities (O'Reilly et al., 2009, Hägglund and Ahlström, 2007, Margalith et al., 2004).
Pregnancy and childbirth have been identified as etiological factors of pelvic floor problems
in a woman´s life (Koelbl et al., 2013). In the first three months postpartum, 33% of women
are reported to experience urinary incontinence, with small changes over the first year post
partum (Thom and Rortveit, 2010). Faecal and flatal incontinence were reported by 10% and
up to 24% of women respectively at six weeks after delivery (Borello-France et al., 2006, Hall
et al., 2003), and by 1% and 26% of women at nine months after vaginal delivery (Zetterstrom
et al., 1999); pelvic organ prolapse stage ≥II was found to have a prevalence between 7.7%
and 56% in the 3-6 months after birth (Diez-Itza et al., 2011a, b, Wai et al., 2011).
The described pelvic floor problems are assumed to be associated with suboptimal pelvic
floor muscle performance. A number of studies found that the pelvic floor muscles of urinary
continent women performed better than those of incontinent women (Hahn et al., 1996,
Baracho et al., 2012, Mørkved et al., 2004, Hilde et al., 2013, Bø, 2003). Pelvic floor muscle
weakness may also be a factor contributing to anal incontinence and pelvic organ prolapse
(Sahlin and Berner, 2007, Mørkved, 2007, Koelbl et al., 2013, Bø and Frawley, 2007) .
Irrespective of pelvic floor symptoms, a reduced pelvic floor muscle performance after
vaginal delivery was demonstrated in the short (Baytur et al., 2007, Marshall et al., 2002,
Hilde et al., 2013, Sigurdardottir et al., 2011) and long-term (Friedman et al., 2012).
5
is recommended as a standard intervention to all women in postpartum care (Abrams et al.,
2010). Training in women without symptoms aims at enhancing pelvic floor muscle
performance as secondary prevention of stress urinary incontinence or other pelvic floor
muscle impairment symptoms later in life. However, Koelbl et al. (2013) temper this
statement by recommending that health providers should carefully consider the cost/benefit of
population based approaches to health professional taught pelvic floor muscle training to all
postpartum women regardless of their continence status.
Midwives and nurses as key professionals in this period of high pelvic floor vulnerability in a
woman´s life need to be knowledgeable and proactive in promoting pelvic floor health and
thus, the proposed study aims to provide all health care workers with useful information for
pelvic floor care.
Background
To promote pelvic floor health in women after childbirth, the commonly recommended
intervention to treat and prevent pelvic floor problems is instructing women to perform pelvic
floor muscle exercises (Boyle et al., 2012, Mørkved and Bø, 2014). An alternative pelvic floor
muscle rehabilitation method consists in the vaginal use of cones or balls. These devices can
be cylinders either conical at one end or rounded at both ends, or ball-shaped, and they come
in different weights (to be increased during training) and sizes (Bø & Aschehoug 2007).
According to Bø (2007), their assumed working mechanism consists of reflexive or voluntary
contractions of the pelvic floor muscles to prevent the inserted cones/balls from slipping out,
thus enhancing pelvic floor muscle performance. Additionally, sensory (by feeling pressure
from the cone) and kinesthetic (by feeling the cone move downwards) biofeedback teaches
6
(Chiarelli & Moore 2008). Vibrating vaginal balls are considered to provide further
stimulation by vibrations caused mechanically by a loose inner ball when the woman is
moving with the ball inserted (Glavind 2001).
A systematic review (Oblasser et al., 2015) showed a dearth of evidence on the effectiveness
of vibrating balls to enhance pelvic floor muscle performance or urinary continence in the
postpartum period. A secondary analysis of original data of the only included study (Wilson
and Herbison, 1998) in the aforementioned systematic review suggests that use of
non-vibrating weighted vaginal cones might be helpful for urinary incontinence after childbirth but
the evidence was limited. Glavind (2001) studied the associated outcomes of vibrating vaginal
ball use in women with stress urinary incontinence in a clinical trial but this was not specific
to the postpartum period. Within the methodological limits of only ten women in a single
group, the study showed encouraging results and the author recommended further research on
ball effectiveness. Thus, all available data correspond with the results of a Cochrane review
on non-vibrating weighted vaginal cones (including balls) for women with urinary
incontinence (not specifically post partum) which provided some evidence that weighted
vaginal cones are more useful than no active treatment for urinary incontinence, and might be
of similar effectiveness to pelvic floor muscle exercises. This review recommended larger,
high-quality trials to reach a more firm conclusion on their effectiveness (Herbison and Dean,
2013).
Thus, while pelvic floor care is an important issue for all women after childbirth, there is
limited evidence to evaluate the use of vibrating vaginal balls. Such vibrating balls are
available for sale in Austria (see e.g. fun factory, no date) and seem to be known and accepted
among women as an option to strengthen the pelvic floor muscles after childbirth; also
women and professionals provide anecdotal evidence about their effectiveness. Such a device
7
would be practical and time saving and give women more choice about pelvic floor care.
Conversely, it is important not to recommend and spend money on an ineffective device.
Research can scientifically examine whether these devices are effective and thereby further
evidence-based practice.
The best research design to determine the effectiveness of an intervention is a randomised
controlled trial (RCT) (OCEBM Levels of Evidence Working Group, 2011). As a full RCT
needs careful preparation, and more basic research on the intervention is needed, a feasibility
trial is proposed here. The novelty of the proposed research lies in the particular suggested
working mechanism of the balls, pelvic floor muscle performance as an outcome measure, the
greater intended number of participants than in Glavind´s (2001) study, the targeted use for
women after childbirth, and in its methodological purpose.
THE STUDY
Aims
The proposed study aims to assess practical issues and feasibility for good design of a future
full RCT which will determine the effectiveness of vibrating vaginal balls to improve pelvic
floor muscle performance in women after childbirth. Furthermore, the feasibility trial will
monitor any potential harms of the experimental intervention; explore women´s perspectives
8
Research questions
How can an RCT on the effectiveness of vibrating vaginal balls to improve pelvic
floor muscle performance after childbirth be prepared and performed best?
How many participants would be needed for a full trial to test effectiveness?
What are women´s perspectives on and experiences with the interventions and the
trial?
Is there any harm associated with the experimental intervention?
Objectives
Determine feasibility of a future full trial
Explore different recruitment strategies
Test appropriate outcome measures
Determine descriptive characteristics of the future RCT´s outcome measures
Explore effect sizes
Increase clinical experience with the experimental intervention
Collect harms-related data of the experimental intervention
Increase knowledge on theoretical basis of the experimental intervention
Investigate women´s perspectives on and experiences with the interventions and
the trial
Determine concordance with the interventions and identify any adaptations needed
to increase this
9
Design/methodology
The study will be a single blind, randomised controlled feasibility trial with two parallel
groups (use of vibrating vaginal ball versus pelvic floor muscle exercises).
Sample
The opportunity and volunteer sample in Vienna will be hospital and community based. The
inclusion and exclusion criteria, selected to include healthy women, control for confounding
factors, minimise the risk of infection, and for pragmatic and ethical reasons, are shown in
table 1. Recruitment will be explored via different routes:
a) Postnatal wards of Vienna General Hospital
b) Delivery suite of Vienna General Hospital
c) Community midwives
d) Practices of obstetrician-gynaecologists
e) Midwifery Centre Vienna (Hebammenzentrum Wien) and Nanaya (parenting centre)
f) Relevant websites (e.g. the Austrian Midwifery Board website, or facebook)
Professionals at the different sites will approach eligible women, or leaflets will be placed. If
possible, a potential participant´s phone number is noted so that CO can actively approach
her, otherwise women have to approach the researcher themselves. Web recruitment also
relies on self recruitment of women. If a woman´s interest and eligibility is confirmed at an
initial contact with CO (mostly a phone call), she is sent an information/consent form via
e-mail or e-mail in case she does not have it yet (this depends on recruitment route). Not earlier
than 7-10 days after she has received the form, the potential participant is called to ask if she
is still interested and to answer possible questions. If interested in participation, a personal
meeting between her and CO on the venue of her choice (her home, hospital or a public place
10
check by her obstetrician-gynaecologist. At this meeting, the study will be fully explained and
details can be clarified. If applicable, the participant information/consent form will be signed,
and data collection will start.
56 women from the accessible population are planned to be recruited from February 2015 to
February 2016. This sample size was based on the following rationales for feasibility and pilot
studies:
i. A sample size of 55 is recommended for pilot studies by Sim and Lewis (2012) to
determine descriptive characteristics of outcome measures for calculation of sample
size for the main trial.
ii. Using the formula for calculating sample sizes to be able to determine feasibility
proportions by Hooper (no date), the determination of a rate of ≥ 80% with a 95%CI
from 70-90 (the lowest feasibility rate in this trial, see feasibility criteria in table 2)
requires a sample size of 56.
Treatment assignment
Allocation of participants to trial groups will be done by randomisation in blocks of different
size. Blocked randomisation promotes an even distribution of participants, especially in small
samples where only part of the intended sample size may be recruited as in the proposed
study; different size of blocks will help prevent selection bias by keeping the investigator
masked to the size of each block and thus unable to predict allocation (Efird, 2011). To obtain
more information about the experimental intervention (Duan, 2013), the allocation ratio is
skewed towards the ball group with two thirds (37) of participants allocated to the
experimental and one third (19) to the comparison arm.
The allocation sequence will be produced via an appropriate computer programme accessible
11
participant identification numbers and containing the codes generated by the computer
programme will be prepared in advance. Each time a participant is randomised following
consent by CO, the envelope with her participant identification number will be opened.
Interventions
The experimental intervention is the use of the EC licensed pelvic floor muscle training ball
Laselle Kegel Exerciser 28g (Intimina, 2014). The ball is inserted into the vagina and left for
15 minutes daily in the first week, and if well tolerated 30 minutes daily from the second
week onwards. To achieve the vibrating effect, the balls are worn while moving – performing
everyday tasks or going for a walk. The balls are not to be worn during menstruation or
intercourse, other contraindications are covered within the exclusion criteria (table 1).
Detailed instructions for use are given to participants in the information/consent form and
explained verbally by CO before signing. The participants will neither be prohibited nor
encouraged to do the pelvic floor muscle exercises they have been recommended by their
health practitioners.
Comparison will be made to basic usual care after childbirth in Austria, which is the routine
recommendation to do pelvic floor muscle exercises. Although courses for supervised pelvic
floor muscle training for women after childbirth are available, many women do not attend,
and if they do, costs are not defrayed by the health insurance system. Participants will be
asked to continue/start the pelvic floor muscle exercises they routinely were recommended by
customary written instructions from their health professionals after birth. If women have not
been given an instruction sheet, they will be given one designed for this study and the
techniques will be explained to them. There are no contraindications to this intervention.
Duration of the interventions is projected for 12 weeks, in accordance with the recommended
12
(National Collaborating Centre for Women´s and Children´s Health, 2013) and with Glavind
(2001). To chart concordance, participants will be asked to keep a training diary to note
if/how long the ball was worn or if/how often the exercises were performed. Concordance is
defined as adequate when at least 80% (in days) of the prescribed exercise sessions have been
completed. This diary is also likely to enhance participants’ retention within the study and
concordance with the intervention, as well as planned phone calls for adverse events
monitoring.
Data collection
Table 3 summarises which data will be collected when and how. All except one of the data
collection tools have been designed specifically for this study. The questionnaire to collect
participant reported pelvic floor outcome measures contains a self-designed section with
measures of pelvic floor muscle performance and vaginal/bowel symptoms taken from the
pelvic floor questionnaires by Dietz et al. (2012), Thibault-Gagnon et al. (2014) and Bässler
and Kempkensteffen (2009) (consent from authors obtained). Original questions were adapted
to suit the purpose of this study, in consideration of patient and public involvement (PPI, see
below) input and to enable a consistent questionnaire design. It also includes the validated
German International Consultation on Incontinence Modular Questionnaire – Urinary
Incontinence Short Form (ICIQ-UI SF) (Avery et al., 2004). Perineometric measurements
comprise vaginal resting pressure, maximum pressure and endurance. Correctly performed in
a standardised manner, they have been shown to be valid and reliable (Bø et al., 1990b,
Frawley et al., 2006, Bø et al., 1990a, Hundley et al., 2005). Study documents will be made
available with the report of the study itself.
Blinding (masking) of participants, personnel and outcome assessors is recommended to
avoid risk of bias in clinical trials (Higgins et al., 2011). To avoid detection bias, the assessor
13
allocation information by asking participants not to reveal their intervention during
measurement. Masking of participants (by withholding information about the alternative
options) would make the trial flow more complicated with this intervention, and there is a
large risk of unmasking as mothers might meet and talk to each other. Therefore, participants
are not masked. CO, assigning participants to interventions, explaining procedures, doing
baseline data and participant reported outcome data collection and interviews, as well as
analysis, will not be masked.
Table 4 shows the study flow from a participant´s view. 18 women of the vaginal ball group
and 10 of the exercises group will be interviewed by structured interviews before the
intervention to examine their views on the intervention and the trial, and after the intervention
to gain their perspectives on and now experiences with the intervention and their participation
in the trial. From these interviews, a questionnaire will be developed to anonymously survey
the following participants and to pilot it for the main trial.
The 28 survey participants will be offered the questionnaire to complete after their last
meeting with the researcher. If the participant has Internet access, she will be given the online
link to complete the electronic version of the questionnaire. Otherwise, it will be handed out
in paper form with an addressed and stamped envelope and expected to be sent back via mail.
Two global text message reminders will be sent one and two weeks later to enhance response
rate (QuestionPro Survey Software, 2015).
Feasibility variables will be calculated according to the criteria in table 2. Any woman who
does not wish to participate or asks to withdraw from the study will be given an opportunity to
14
Data management and analysis
Data will be collected on paper or via online forms created via formAssembly at City
University London, and will subsequently be entered into a computer database. To avoid entry
errors, data will be double-checked on a later day. Data will be processed and analysed using
the currently available versions of Excel and/or SPSS (IBM Corporation, 2012/13), with
support from a statistical advisor.
Feasibility criteria and resources calculation will be analysed descriptively, as well as baseline
data, concordance and pelvic floor outcome measures. Groups will be compared by
appropriate tests in a superiority analysis. Due to the nature of a feasibility trial, there will be
no hypothesis testing (Eldridge, 2013, Feasibility and Pilot Studies, no year), and the results
from statistical tests are not planned to be published except within the doctoral thesis. For
continuous data, these will be repeated measures analysis of variance (ANOVA) or
independent t-test for parametric, and linear regression analysis or Mann-Whitney U test for
nonparametric data respectively. For dichotomous data, these will be logistic regression or
Fisher´s exact test. If a large imbalance between groups is found for a confounding factor,
statistical adjustment will be made by using ANCOVAs for the planned ANOVAs, or by
using stratified analyses for the other tests. The intention-to-treat analysis will exclude
participants who are found to be ineligible after randomisation. Missing values will be dealt
with according to their nature and with the technique appropriate to the reason why they are
missing. The findings from these group comparisons are intended to refine hypotheses and
better understand the needs of a full trial in terms of best primary outcome measure and
sample size calculation.
Qualitative data will be processed and analysed following the principles of processing
15
content analysis will create codes for answers to open questions and categorise answers into
these codes to condense information.
Ethical considerations
The ethical principles (according to the World Medical Association, 2013) of doing no harm,
participants´ right to autonomy, information and data protection, as well as safety of the
researcher were considered. The study was approved by the relevant ethics committees (table
5). The trial will be conducted in accordance with the research protocol, and any amendments
if needed, will be clarified with the ethics committees and communicated at the trial registry.
Participants must provide written informed consent. This will be obtained by CO in a personal
meeting with each prospective participant, after having allowed her enough time to read the
information/consent form and to reflect about participation, and after thorough discussion of
all unclear issues. The consent form was created according to the template by the lead ethics
committee and is kept in lay language. Confidential secure handling of personal data is
regulated by the Austrian Data Protection Act (Bundeskanzleramt Österreich, 2015) and by
City University London´s requirements for retention, acces and storage of the data.
Safety of medical devices used
Laselle Kegel Exercisers by Intimina/LELO are of body-safe, phthalate-free FDA-approved
silicone and ABS (Intimina, 2014), and they are a EU/EEC licensed medical device class 1
(Council Directive 93/42/EEC), as is the vaginal measurement probe. The handheld
microprocessor of the measurement device PeritronTM (from Laborie) does not have a CE
16
Adverse effects of interventions
The use of vaginal pelvic floor balls seems to be a safe method of training. In the studies that
mention adverse effects of balls or cones, these are rare and not serious. In a German
pharmaceutic consumer survey on the Laselle Kegel Exercisers (Test-Club-Bericht, 2013), no
adverse effects were reported (cave: consumer journal). Glavind (2001), using another
(double) model of vibrating vaginal balls, described a slight vaginal irritation in one of her ten
participants. In their systematic review on weighted vaginal cones, Herbison and Dean (2013)
mention discomfort and bleeding as reasons for women dropping out of treatment. Another
adverse effect identified with cones is occasional muscle soreness at the beginning of the
training (Fischer et al., 1996), and Bø et al. (1999) reported one woman with abdominal pain
and two with vaginitis (out of 29). However, Glavind (2001) and Bø et al. (1999) included
women up to 59 and 70 years, respectively, which might influence adverse effects. An
Austrian physiotherapist having been working with pelvic floor training balls since 15 years
confirms that some women have experienced bleeding, but she never has seen a case of
vaginal infection (Udier, 2014).
Pelvic floor muscle exercises seem to be a safe method of training, although the majority of
studies do not consider reporting adverse effects (Boyle et al., 2012, National Collaborating
Centre for Women´s and Children´s Health, 2013). In one study with 107 participants, pain
(once) and an uncomfortable feeling during exercise (three times) were identified as adverse
effects (Lagro-Janssen et al., 1992).
The pelvic floor measurement performed for this study is not known to carry any risks, and
17
Adverse events
Expected adverse events in the experimental group are discomfort, slight muscle soreness or
pain (from too much training), slight vaginal bleeding (rarely), vaginal irritation (very rarely)
or infection (very rarely). Expected adverse events in the comparison group are an
uncomfortable feeling during exercise (rarely) or pain (very rarely). A policy of active and
passive surveillance will be applied to monitor expected and unexpected adverse events after
uptake of the assigned intervention:
Participants will be informed in oral and written form about potential adverse effects
and their warning signs.
To check for adverse events, participants will be phoned at fixed intervals. The content
of the call is standardised and the contacts will be documented.
Adverse events assessment is part of the final interview and survey questionnaire.
Transfer to necessary care will be arranged should the need arise, and termination of
participation will be recommended to a participant when there is vaginal infection, occurrence
of repeated bleeding, or pregnancy. Adverse events recording will comprise type, severity and
number of all events for all participants and will be reported according to interventions.
Serious adverse events (SAEs), as defined by the guidance for clinical safety data
management (European Medicines Agency, 1995), and urgent safety measures will be
reported to both research ethics committees.
Patient and public involvement
In planning the methodological features of this feasibility trial, six women having given birth
18
Research, no date). The ethnic background of these women was Somali, British White, and
Austrian White. Consultation meetings were held between March and July 2014. Study issues
in question at the time of meeting were discussed with the women, such as where best to
recruit participants, their potential worries, number and kind of study contacts, or
acceptability of the experimental intervention and outcome measurements. Their suggestions
were e.g. to stress the importance of the research to potential participants, that Muslim women
might not want to use the balls, to ask a female person for pelvic floor muscle measurement,
or to prepare a paper questionnaire for women who do not have Internet access. Two women
checked the appropriateness and comprehensibility of study documents for participants.
Validity and reliability/rigour
As advised for the chosen design (Eldridge, 2013, Williams and Lecouturier, no year,
Feasibility and Pilot Studies, no year), the study has clear feasibility aims and pre-defined
progression criteria, and there will be no hypothesis testing. A scientifically justified
calculation of the sample size for pilot/feasibility studies (Sim and Lewis, 2012, Hooper, no
date) determined the appropriate number of participants, who are specified via inclusion and
exclusion criteria. The key elements ensuring validity and reliability of the future randomised
controlled trial – random group allocation, allocation concealment and masked assessment
(Meinert, 2012) – are applied. Even if the participants and researcher will be aware of group
allocation, allocation can be concealed from the masked outcome assessor. The use of two
methods of data collection – participant reported pelvic floor outcomes and technical
measurement – within the same study and the same research approach will enhance outcome
information on the variable pelvic floor muscle performance by methodological triangulation
(Denzin, 2009). The ICIQ-UI SF is a validated questionnaire, and the perineometric
19
by qualitative data to take into account participants´ points of view and experiences.
Instruments developed for this study were submitted to a PPI process and will be tested
further during the current study. PPI work also informed the other features in the preparation
of the study. Data entered manually from collection forms into the computer database will be
checked on a later day to avoid entry errors. Confounding variables will be controlled for by
considering them as co-variables in the analysis. As this is a feasibility trial, a data monitoring
committee is not needed. The compilation of this trial protocol and the present report
correspond to the SPIRIT guidelines (Chan et al., 2013).
Registration, reporting and dissemination
The trial was registered based on the protocol version 2 from 19 October 2014. The
registration items from the World Health Organization Trial Registration Data Set (WHO,
2015) are presented in table 5. Reporting and dissemination of the results is planned via
completion of the thesis, professional conferences, publications in appropriate journals, and to
(PPI) participants. Authorship eligibility guidelines as recommended by the International
Committee of Medical Journal Editors (2015) will apply.
DISCUSSION
The proposed feasibility trial will collect information to prepare a future RCT. The novel
aspect of this study, as far as known, is that the proposed study is the first one to look at the
use of vibrating vaginal balls specifically during the postpartum period. The quantitative and
qualitative information gained from this feasibility trial will be useful for midwives, nurses,
20
health.By testing the planned processes it will also be useful for research in setting the basis
and enhancing the rigour of the confirmatory future RCT to determine the effectiveness of the
device of interest.
Limitations
A limitation inherent in the proposed research design is that no results about the effectiveness
of the device researched will be available after completion of this study. The planned
non-probability sampling approach of an opportunity and volunteer sample at a single city will
reduce generalisibility of the results. Participants cannot be masked for the researched
interventions, and contamination of interventions might be found. 12 weeks may proof an
intervention period too long for participants, and concordance thus may be difficult to
achieve.
CONCLUSION
The results of this trial will provide information about the features and feasibility of a future
RCT concerning issues of trial design, recruitment, interventions, methods of measurement,
data collection, and data analysis. They will also provide information about any potential
harms, and participants´ views of and experiences with the interventions and participating in a
trial of it.
The interpretation and discussion will focus on feasibility, taking into account the stated
feasibility criteria (table 2), sources of potential bias or imprecision, and barriers or facilitators
to participation and concordance. It will be concluded that the planned full RCT to determine
21
feasible with modifications or not feasible. If not feasible, the realisation of a full RCT must
be abandoned. If feasible with modifications, necessary protocol alterations for the full scale
trial based on the results of the feasibility trial will be clearly stated. If feasibility is shown,
funding for the full trial will be sought.
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